Bodipy probes to study photoinduced oxidations in model membranes, organelles, and cells

• Grant number: 23/06657-3
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: September 17, 2023
• End date: September 16, 2024
• Field of knowledge: Biological Sciences - Biophysics - Radiology and Photobiology
• Principal Investigator: Mauricio da Silva Baptista
• Grantee: Márcia Silvana Freire Franco
• Supervisor: Gonzalo Cosa
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: McGill University, Canada
• Associated to the scholarship: 22/07047-1 - Photoinduced oxidations in model membranes, organelles, cells and skin mimics: molecular mechanisms and protection strategies, BP.PD

Abstract

Sterols, referred to as the third lipid class, bear the essential triterpenoid scaffold, that ensure fluidity and flexibility to cell membranes, and serve as signaling important molecules crucial in growth, development and differentiation of organisms. The 7-Dehydrocholesterol (7-DHC) is a biosynthetic precursor of cholesterol and vitamin D3, and ergosterol. Similar to the polyunsaturated fatty acids (PUFAs), sterols oxidation has a relevant path in the pathophysiology of common diseases, and is involved in cell death pathways covering necrosis, apoptosis, oxytosis and ferroptosis; however, therapeutic effects can also be achieved in treatments with photodynamic therapy (PDT). Membrane permeabilization under PDT conditions occurs via transmembrane pore opening, and phase contrast microscopy of giant unilamellar vesicles (GUVs) have allowed the phenomenological observation of membrane expansion, pore opening as well as the evaluation of the membrane dynamics during the oxidative challenge. Regarding the investigation of 7-DHC, Cholesterol, and Ergosterol mechanistic protection against photodamage membrane, the use fluorogenic BODIPY±Tocopherol probe analogues will be applied to monitor reactive oxygen species, allowing a fundamental study on the chemical and physical properties of membrane associated to their composition. (AU)